POS0633 HIGH SENSITIVITY TROPONIN I IS ASSOCIATED WITH FOCAL FIBROSIS AS DETECTED BY CARDIAC MR IN EARLY, TREATMENT-NAIVE RA
Authors: R. Shukla, R. Ark, A. Burska, S. Plein, M. H. Buch
Journal: Annals of the Rheumatic Diseases (2022)

Background RA individuals are known to have excess CVD risk, equivalent to that of type 2 diabetes mellitus 1 . We recently reported vascular and myocardial abnormalities on cardiac magnetic resonance imaging (CMR) in an early RA cohort compared with control subjects, and improvement with DMARD treatment 2 . Non-invasive assays for high-sensitivity troponin and NT-pro-BNP have been evaluated in RA cohorts. No study has investigated these in early, treatment-naïve RA and in association with subclinical CMR findings. Objectives In a treatment-naïve, early RA trial cohort, we examined serum cardiac markers of ventricular stretch (NT-pro-BNP) and myocardial injury (high-sensitivity troponin-I (hs-Tn-I)) and change with treatment, and whether these associated with cardiac MRI abnormalities. Methods In CADERA (a unique early RA RCT derived study), out of a total of 120 patients randomised to either first-line TNFi+MTX (n=60) or MTX and conventional synthetic DMARDs (n=60), 81 subjects with no previous history of CVD or diabetes and with only a maximum of 1 other traditional risk factor, underwent baseline and year 1 CMR. Corresponding levels of NT-pro-BNP (pg/ml) and hs-Tn-I (ng/L) were measured at baseline and year 1. CADERA reported CMR measures of vascular stiffness [aortic stiffness index (AoSI), and aortic distensibility (AD)]; tissue oedema/fibrosis [native T1 values (T1), myocardial extracellular volume (ECV), and late gadolinium enhancement (LGE)] and ventricular function 2 . Bayesian linear and logistic regression models with mixed effects for overall data were used to test association between serum cardiac markers and CMR parameters. Results CADERA trial already reported baseline demographics and comorbidity data of patients. The most common risk factor was smoking history (55%) followed by hypertension (7%) and family history of ischaemic heart disease (5%) 2 . 7 patients had abnormal findings on LGE imaging at baseline and 4 at year 1. 2 From baseline to year 1, NT-pro-BNP remained within normal limits although a numerical improvement was noted at year 1(76.4 to 59.4, p = 0.038). Hs-Tn-I was within normal limits (&lt;3ng/L) with no significant change noted (1.62 to 1.7). At baseline, median hs-Tn-I was 2 (IQR 1.4 - 3.05) in patients with abnormal LGE findings compared to 1.60 (0.95 – 2.52) in those without (p = 0.3). At year 1, median hs-Tn-I was 2.70 (IQR 1.08 – 4.82) in patients with abnormal LGE findings versus 1.7 (IQR 1 – 2.5) in those without (p = 0.5). Table 1 outlines the association of serum cardiac markers with CMR parameters. At baseline, hs-Tn-I positively associated with LGE. This association was also demonstrated when considering overall data (baseline + week 48). Association of NT-pro-BNP with CMR was not significant. Table 1. Association of serum Hs-Tn-I with CMR parameters (posterior estimates with 95% credible intervals reported) CMR parameter Hs-Tn-I Overall Baseline Year 1 Measures of myocardial tissue oedema/fibrosis LGE 0.56(0.1 to 1.11 ) 0.6(0.04 to 1.27 ) 0.54(-0.13 to 1.17) T1 -4.42(-10.5 to 1.5) -0.38(-6.7 to 6.2) -6.02(-14.9 to 3.15) ECV 0.002(-0.04 to 0.08 0.001(-0.05 to 0.07) 0.001(-0.04 to 0.04) Measures of vascular stiffness AoSI 0.01(-0.23 to 0.25) 0.05(-0.22 to 0.33) 0.05(-0.33 to 0.42) AD -0.05(-0.23 to 0.13) -0.02(-0.18 to 0.14) -0.06(-0.37 to 0.25) Conclusion Our data suggest hs-Tn-I is within normal limits in a treatment-naïve, RA cohort but with numerical differences that associated with presence of focal fibrosis on CMR. Modest numbers of those with focal fibrosis may account for normal range values for hs-Tn-I. References [1]Peters MJL, Van Halm VP, Voskuyl AE, et al. Does rheumatoid arthritis equal diabetes mellitus as an independent risk factor for cardiovascular disease? A prospective study. Arthritis Care Res. 2009;61(11). [2]Plein S, Erhayiem B, Fent G, et al. Using cardiovascular magnetic resonance to define mechanisms of comorbidity and to measure the effect of biological therapy: the CADERA observational study. Effic Mech Eval. 2021;8(4):1–42. Disclosure of Interests None declared